Grand Canyon

The Grand Canyon (Hopi: Ongtupqa; Yavapai: Wi:kaʼi:la, Spanish: Gran Cañón) is a steep-sided canyon carved by the Colorado River in the state of Arizona in the United States. It is contained within and managed by Grand Canyon National Park, the Kaibab National Forest, Grand Canyon-Parashant National Monument, the Hualapai Tribal Nation, the Havasupai people and the Navajo Nation. President Theodore Roosevelt was a major proponent of preservation of the Grand Canyon area, and visited it on numerous occasions to hunt and enjoy the scenery.

The Grand Canyon is 277 miles (446 km) long, up to 18 miles (29 km) wide and attains a depth of over a mile (6,093 feet or 1,857 meters). Nearly two billion years of Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted. While some aspects about the history of incision of the canyon are debated by geologists, several recent studies support the hypothesis that the Colorado River established its course through the area about 5 or 6 million years ago. Since that time, the Colorado River has driven the down-cutting of the tributaries and retreat of the cliffs, simultaneously deepening and widening the canyon.

Toroweap Overlook

Toroweap Overlook (also known as Tuweep Overlook or Toroweap Point) is a viewpoint within the Grand Canyon National Park in Arizona, United States. It is located in a remote area on the North Rim of the Grand Canyon, 55 miles west of the North Rim Headquarters (but 148 miles by road). The overlook is the only viewpoint in the National Park from where the Colorado River can be seen vertically below. The overlook stands 3,000 feet above the river.

Terminology

Toroweap and Tuweep are used more or less interchangeably. The term Tuweep, a Paiute word for "the earth", was used for an early Mormon settlement in the valley, and is now used by the National Park Service to refer to the area. Toroweap, a Paiute term meaning "dry or barren valley", strictly refers to the valley and the overlook.

Geology

At Toroweap the layer of soft Hermit Shale is about 800 feet thick, much thicker than farther east. Erosion of this layer formed the broad Esplanade Platform on the resistant Esplanade Sandstone. Further erosion formed a deep side canyon, draining into the Colorado. The Toroweap Fault underlies the valley, and volcanic activity along the fault resulted in the Uinkaret volcanic field, from where lava flows filled the side canyon. Sediment and lava flows eventually filled the side canyon to the level of the Esplanade Platform. The high outer rim of the Grand Canyon is absent at Toroweap, and the overlook can therefore be reached by a road which follows the Toroweap Valley to the brink of the Inner Gorge.

National park

A national park is a park in use for conservation purposes. Often it is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns. Although individual nations designate their own national parks differently, there is a common idea: the conservation of 'wild nature' for posterity and as a symbol of national pride. An international organization, the International Union for Conservation of Nature (IUCN), and its World Commission on Protected Areas, has defined "National Park" as its Category II type of protected areas.

While this type of national park had been proposed previously, the United States established the first "public park or pleasuring-ground for the benefit and enjoyment of the people", Yellowstone National Park, in 1872. Although Yellowstone was not officially termed a "national park" in its establishing law, it was always termed such in practice and is widely held to be the first and oldest national park in the world. The first area to use "national park" in its creation legislation was the US's Mackinac Island, in 1875. Australia's Royal National Park, established in 1879, was the world's third official national park. In 1895 ownership of Mackinac Island was transferred to the State of Michigan as a state park and national park status was consequently lost. As a result, Australia's Royal National Park is by some considerations the second oldest national park now in existence.